The top one is "HD Verified," which means users should be able to watch videos in HD (at least 720p) with fast load times most of the time. To get the rating the operator's network has to perform at that level 90 percent of the time. The sustained speed needed to qualify is over 2.5M bps.

The other two ratings are "Standard Definition" and "Lower Definition". They mean users can watch videos in standard definition (at least 360p) with moderate load times or with a resolution lower than 360p. Videos will also load slowly and may stop to re-buffer over networks that have the lowest rating.

The rating for an ISP can be split into various time slices -- for example, hour, day or week -- as well as different geographical levels. Google's goal was to present a rating that "is meaningful, easy to understand and one that closely reflects the real world Internet experience," the company said.

The ratings take into account many users in a given area, rather than measure just one household's connection. Google said it will only show the results for a geographic area big enough to have a lot of users, and emphasized that all samples are anonymized and no personal information is stored or used.

The timing of the announcement is interesting, since it was only last week that a U.S. appeals court struck down the Federal Communications Commission's net neutrality rules. Even though the Video Quality Report isn't yet available in the U.S., the service could eventually work as a deterrent to ISPs that are tempted to prioritize their own video offerings over Internet-based ones like YouTube.

The company didn't give any details on when the report will become available to users outside of Canada. For now, the site just says "results from your location are not yet available" if you try to use it in other countries.

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